Field of the Invention
The present invention relates to a DC-DC converter, and particularly to a technique for reducing current consumption under light load.
Background Art
Recently, the power consumption of an electronic device equipped with a battery has been increasingly reduced. Particularly, an electronic device such as a smartphone, a mobile device, or a wearable device has been required to reduce power consumption more and more in order to make the drive time longer. Therefore, a semiconductor integrated circuit incorporated in the electronic device is also required to reduce power consumption significantly.
In the meantime, the safety of an electronic device, such as a mobile device directly handled by a person, not to affect the human body adversely like an explosion or electric shock is particularly required.
For example, a DC-DC converter incorporated in a battery-driven electronic device to operate at the battery voltage includes an overheat protection circuit that stops the operation when the chip temperature in a semiconductor integrated circuit rises and reaches a temperature equal to or higher than a predefined temperature, a supply voltage monitoring circuit that prevents the malfunction of an internal circuit when the battery voltage drops significantly, and the like (for example, see Patent Document 1).
[Patent Document 1] Japanese Patent Application Laid-Open No. 2005-328589